[Sane-analysis] Minutes of Jan 27 2010 Meeting

[Narbe Kalantarians]

_*James:*_ Worked on polarization analysis. IN ratios of offline/online 
polarization there were some drops, possibly from drift in magnetic 
field. Looked at chi-square of NMR poly-fit.
https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Polarization_Drop_in_Offline_Analysis

Working on improving this fit by possibly using quadratic with a 
Lorenztian. Oscar mentioned that such a fitting scheme was used for RSS
http://twist.phys.virginia.edu/~or/target/BOT_H_TE.EPS


_*Whit:*_ Looked at raw ADC data for Cherenkov to investigate missing 
ADC hits. Mentioned that this could be from cross-talk resulting from 
threshold settings. Mark mentioned that Cherenkov ADC (cer_adc) usually 
displays a peak around 0 with a long tail that is noticeable at log 
scale.    
https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Gas_Cherenkov_Detector#Data


_*Jon: *_Will start working on BigCal (block to block) timing 
calibration. An initial time-walk correction was implemented in the 
beginning but does not account for some subtleties such as block 
overlaps. Will contact Andrew Puckett t osee how he did this for GEPIII.

Started a page on the wiki, listing the ntuple variables along with 
descriptions for them. This is on the main page, under 'Detectors and 
Software'.
 https://hallcweb.jlab.org/experiments/sane/wiki/index.php/SANE_Raw_Ntuple_Variable_Description


_*Anusha:*_ Worked on elastic calibration for BigCal. Looked at deltaE = 
E_HMS - Eclust. Using either older calibration constants or none 
(depending on whter it's ntuple variable eclust or e_clust) there was a 
shift of -370MeV for deltaE. Using newer constants it becomes 250MeV. 
This could possibly due to those constants having been extracted with 
neural network, which is not yet implemented into CVS for the Analyzer.

I can't find the link for the plots. So if anyone does please reply to 
this e-mail with it.


_*Luwani:*_ Started helping with Cherenkov calibrations. After that will 
get more involved with pair-symmetric background investigation.


_*Hovhannes:*_ Finalizing BigCal Energy calibrations. Has over half of 
the data set done and will finish soon. Will focus on the parallel 
portion of the data for the immediate future.


_*Narbe:*_ Altered SANE GEANT(3) to use Peter's latest cross-section 
model (F1F209) in place of MRST2001 for inelastic. Talked with Vahe 
Mamyan about getting radiative corrections for 4.7 GeV.  


There will be an emphasis on getting the parallel data more finalzed to 
get preliminary A_parallel and A_1 to compare with world data. This is 
planned to be done within the next few months.

Next meeting will be Feb 3 2010 at 3:30pm

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